JP Morgan has made a loss because its litigation expenses are huge but don't worry, says chief executive Jamie Dimon, the underlying performance is "really good".

Sorry, but when litigation reserves are $23bn (£14bn), that's just too breezy. The question is whether JP Morgan is too big to be managed competently.

Robert Jenkins, formerly of the Bank of England's financial policy committee, told the FT: "Is it that Mr Dimon is not equal to the task? Or is it that no chief executive can be expected to control such complexity? If it is the former, an executive search is warranted. If it is the latter, then Mr Dimon is a walking argument for breaking up the banks."

It won't happen, of course – but breaking up JP Morgan would be the right thing to do.